package edu.sctu;

import java.sql.*;
import java.util.ArrayList;
import java.util.List;

//类：首字母大写
//方法：首字母小写
//一个类中只有属性与方法
public class DataBase {

//    getUserList方法返回一个集合
    public List<User> getUserList() {

        List<User> userList = new ArrayList<User>();

        try {
            Class.forName("com.mysql.jdbc.Driver");

            Connection connection = null;
            Statement statement = null;
            ResultSet resultSet = null;

            String sql = "select * from t_users";

            connection = DriverManager.getConnection(
                    "jdbc:mysql://localhost:3306/sctu_javaweb_2018?serverTimezone=UTC",
                    "root",
                    "123456");
            statement = connection.createStatement();
            resultSet = statement.executeQuery(sql);

            while (resultSet.next()) {

                int id = resultSet.getInt(1);
                String name = resultSet.getString(2);
                String password = resultSet.getString(3);

                // [封装]在user中
                User user = new User();
                user.setId(id);
                user.setName(name);
                user.setPassword(password);

                userList.add(user);
            }

            statement.close();
            connection.close();
            resultSet.close();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (SQLException e) {
            e.printStackTrace();
        }

    return userList;
    }


}
